This is something I have come across as I try to orchestrate Eine Kleine Nachtmusik for a symphony orchestra. A sort of harmonic ambiguity on Mozart's part. I'm talking about the chord at the repeat of the opening motive. This chord right here:
That is literally just C in 3 octaves. I orchestrated it as a C major chord on that downbeat. But I have been told that what Mozart truly meant by those octave C's is a D7 chord. Um, I don't usually come across octaves in a seventh chord voicing as the only interval. Usually I will at least hear the root, third, and seventh being played simultaneously or possibly the root, fifth, and seventh. Just the tritone alone implies a diminished harmony and just the perfect fifth alone implies a major harmony. A whole phrase in octaves, I normally see that in one of 2 situations:
- Confirmation of the tonic, old or new
- Quiet phrase that is then played again with dynamic intensification(an example of this from Mozart is in Symphony no. 25 in G minor)
This is neither of these 2 situations. Of course the tonic is confirmed, it is the first 4 bars. Mozart isn't going to diverge from the tonic that quickly And it isn't quiet and then intensified, it is a full blown forte followed by a quiet phrase. And the C's in octaves, well C is part of multiple chords in G major, but the most likely ones are D7 and C major.
I orchestrated the downbeat as a C major chord and it sounds good. I try to orchestrate it as a D7 and it gets nasty sounding in the orchestra. This here is my C major orchestration of that downbeat:
Just to make it clear, the image was taken with the instruments being in concert pitch, so I haven't written the Clarinet, Trumpet, and Horn parts wrong.
If I try to orchestrate it as a D7, the strings being in octave C's like in the original score really nasties up that D7 by emphasizing the chordal seventh. And yet I get told that I should orchestrate it as a D7, per Mozart's intentions. But, to me, it isn't clear whether Mozart intended the downbeat to be a D7 or a C major chord because of the octave C's and nothing else.
Did Mozart intend this as being a D7? If so, then how could I orchestrate that chord to be a D7 without the chordal seventh making it sound nasty(I do have the strings playing the original notes, those octave C's that I keep mentioning)? Or is my interpretation of the octave C's as a brief C major chord within a melodic D7 just as valid and thus I shouldn't change anything about how I orchestrate that chord?